In recent years, various types of data processing apparatuses, such as personal computers (PCs), PDAs, tablet computers and smartphones, have been developed.
Generally, to activate such a data processing apparatuses, the password known to only the authenticated user should be input to the apparatus in some cases.
Assume that the authenticated user of the data processing apparatus has informed any other person of the password, because the apparatus needs to be activated at a specified time only. Then, the person who now knows the password may thereafter activate the data processing apparatus.
That is, anyone who knows the password can activate the data processing apparatus that can be activated only if the password is input to it.
This is undesirable in consideration of data security. Some measures must be taken to enable only the authenticated user to activate the data processing apparatus.